Device for changing the gears automatically on a synchronized gearbox

Abstract

A processing device capable of starting the sequence of the speed change operations automatically in the gearbox of a vehicle, such as the automatic transmission of a truck. A first comparator (302) compares the data received from a gearbox condition detecting device (500) and that received from a speed ratio selection device (200). In the event of a difference, the comparator (302) sends to a gearbox control device (400) either a pulse for increasing by one speed ratio, or a pulse for decreasing by one speed ratio.

We claim: 
     
       1. A processing device for automatically controlling changes of speed in a synchronized gearbox associated with a clutch of a vehicle, comprising, in combination: a gearbox having change members;   a gearbox control device (400) operatively connected with and controlling said change members of said gearbox;   a device (200) for selection of speed ratios;   a device (500) for detecting the condition of said gearbox;   a first comparator (302);   an electronic assembly including logic elements;   said electronic assembly having an input section which includes said first comparator (302) operably and electrically connected between said speed ratio selection device (200) and said gearbox condition detecting device (500);   said electronic assembly having its output operably and electrically connected to said gearbox control device (400) for controlling said change members of said gearbox;   said input section of said electronic assembly also including a memory device (301) for the temporary storage of the code of a selected ratio; and   said memory device (301) being operably and electrically connected between said speed ratio selection device (200) and said first comparator (302).   
     
     
       2. A processing device for automatically controlling changes of speed in a synchronized gearbox associated with a clutch of a vehicle, comprising, in combination: a gearbox having change members;   a gearbox control device (400) operatively connected with and controlling said change members of said gearbox;   a device (200) for selection of speed ratios;   a device (500) for detecting the condition of a gearbox;   a first comparator (302);   an electronic assembly including logic elements;   said electronic assembly having an input section which includes said first comparator (302) operably and electrically connected between said speed ratio selection device (200) and said gearbox condition detecting device (500);   said electronic assembly having its output operably and electrically connected to said gearbox control device (400) for controlling said change members of said gearbox; and   said first comparator (302) comprising a four-bit binary comprator.   
     
     
       3. A processing device according to claim 1, wherein: said speed ratio selection device (200) selects a ratio code and transmits said selected ratio code to the input of said temporary storage memory (301);   said gearbox condition detection device (500) produces a gearbox condition code and transmits said gearbox condition code to said first comparator (302);   and, when said first comparator (302) detects a difference between said ratio code and said gearbox condition code, said first comparator (302) emits: a "progression" pulse for increasing by one speed if the selected ratio code is greater than said gearbox condition code; and   a "regression" pulse for decreasing by one speed if the selected ratio code is less than said gearbox condition code.     
     
     
       4. A processing device according to claim 3, wherein: said electronic assembly also includes a validity detector (306) operably and electrically connected to said temporary storage memory (301);   said temporary storage memory (301) transmits an input code to said validity detector (306);   said detector (306) detects the validity of the input code received from the temporary storage memory (301);   said electronic assembly also includes a first AND gate (305), a "Neutral" memory (317), and a temporary storage means (326);   the output of said validity detector (306) and the output of said first comparator (302) are both connected as inputs to said first AND gate (305); and   the output of said first AND gate (305) is electrically connected to and shared between said "Neutral" memory (317), said temporary storage means (326), and said gearbox control device (400).   
     
     
       5. A processing device according to claim 3, wherein: said processing device is used in combination with a gearbox having a collective synchromesh device which is common to all of the ratios of the gearbox; and   said "progression" or "regression" pulse data of a ratio being utilized to control the action of the collective synchromesh device.   
     
     
       6. A processing device according to claim 5, including: an external authorization system which permits the blocking of the process of change of ratio until the collective synchromesh device, which has been suitably and previously controlled by the "progression" or "regression" data, brings about the synchronism.